The invention relates to apparatus and methods for applying a large DC voltage to an electrode to ionize medication-containing mist in order to improve effectiveness of a dosage of the medication to a mammalian patient.
Quite a variety of aerosol dispensers have been provided for distributing or concentrating a fine mist or aerosol of medicated liquid which is used in treatment of illnesses that respond to the inhalation/application of such medications. For example, in treatment of asthma there are many such medications which can be effectively administered by inhalation techniques to inhibit or diminish the respiratory problems of the asthma affected patient. There has been recognition in the prior art of potential benefit from electrically ionizing medicated mist as administered. U.S. Pat. No. 3,502,077 discloses a device in which DC potentials of 20 to 100 volts are applied to "accelerator rings" disposed in a pipe through which a medicated aerosol is passed. U.S. Pat. No. 4,369,776 ionizes water vapor with high voltage pulses across an electrode gap within a tube carrying water vapor; the apparatus is used for dermatological purposes and is referred to as a "dermatological ionizing vaporizer." U.S. Pat. No. 3,194,236 applies a DC voltage of 4,000 to 40,000 volts to liquid which is then converted into an aerosol; in one embodiment described, a charging screen with 100 volts applied thereto is paced in the path of the charged aerosol. U.S. Pat. No. 4,310,474 discloses a device in which a charged vapor stream, for utilization in industrial applications, electrostatically controls a flow of the charged droplets so as to meter them into a vaporizer.
It is known that the unique physiology of the mammalian (particularly human) lung includes a quite substantial effective surface area, including many interstices and linked passages, and any medicated particles or mist droplets entering the lung as an aerosol must pass through these varying linked passages to reach all (or as much as possible) of the effective surface area for maximizing treatment from a given application of the medicated aerosol. None of the devices disclosed in the aforementioned prior patents enable medicated aerosol mist droplets to effectively reach and adhere to all (or nearly all) of the effective surface area of the patient's lungs.
Aerosolized medication can be used in either dry or wet form. The so-called standard metered dose inhalers (MDIs) use Freon or the like as a propellant for powdered medication having a particle size in the order of 2 microns. Also, liquid medications (usually much stronger) can be combined with water and/or a saline solution in a nebulizer device to produce a so-called wet aerosol (e.g., a mist containing liquid medication droplets) which can be administered to a patient, allowing a practitioner to use stronger dosages of medication if desired.